The present invention relates to a tube connecting device for tubes which communicate at connecting tube ends and are coupled together by flanges in a fluid-tight manner.
Gas turbine power plants for fixed installations or for use in aircraft, for example, are equipped with heat exchangers in order to use a portion of the heat contained in the engine exhaust gas stream to heat the combustion air. Tubes and tube connections are required, for example, to conduct the exhaust gas stream toward the tube matrix of the heat exchanger through which the compressed air passes or to conduct it out of the matrix to an exhaust gas duct. They are also required, for example, to guide the heated compressed air emerging from the matrix to the corresponding consumer, in this case, the combustion chamber.
In all of these examples, the affected tubes and their flange connections must often be mounted or run under limited available installation space conditions. The scarce spatial installation conditions must mesh with the requirement that an affected tube flange connection be accessible for assembly and disassembly from only one side of the tube or from above or below, and at the same time satisfy the prerequisites for optimal fluid or gas sealing over the entire circumference of the tube flange connection. Particularly with respect to a hot gas stream to be conducted, a flange connection of this type must also be designed to be resistant to high temperatures and low in wear.
Previously known flange connecting designs, even for rectangular or square tube connecting cross-sections, do meet the requirement for good uniform sealing but also assume the presence of a plurality of screw connections uniformly distributed around the circumference, which therefore essentially necessitate accessibility from all sides to the tube flange connection for assembly or disassembly.
Within the framework of this problem, an object of the present invention is to provide a flange connecting device for tubes which communicate at connecting tube ends and are coupled together by flanges in a fluid-tight manner, which, despite being accessible exclusively from one side, either from above or below, is extremely easy to assemble or disassemble.
Another object of the present invention is to provide a flange connecting device that can be sealed around the entire opposite tube connecting circumference in optimal fashion, and is extremely temperature-resistant.
This and other objects of the present invention are achieved in the present invention by providing a tube connecting device for tubes which communicate at connecting tube ends and are coupled together by flanges with a first tube end having a frame that is open on one side. This frame has a circumferential groove. A second tube end is provided with a circumferential flange that is received in the circumferential groove. A strip covers the open side of the frame and clamps the frame and the flange.
By this invention, it is possible to slide one tube end provided with a flange from the accessible side or from above into the corresponding groove of the frame.
In certain preferred embodiments, a sealing cord is provided which reliably seals three sides of the tube as a result of a complete insertion of the flange into the corresponding frame spanning three sides of the tube.
A seal extending around the entire circumference is provided in preferred embodiments, in simple fashion by a cover strip which is screwed, for example, from above onto the open side of the frame. By this, the flange is tensioned in the circumferential groove of the frame spanning the three sides of the tube end and is also tensioned like a clamp in sealing fashion on the open insertion side to the other part of the frame. By using two or three screws for example, the cover strip and hence the entire flange connection, after the flange has been inserted, can be easily installed or removed, exclusively from one side or from above.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.